"Online Python Tutor is a free educational tool that helps students overcome a fundamental barrier to learning programming: understanding what happens as the computer executes each line of a program's source code. Using this tool, a teacher or student can write a Python program directly in the web browser and visualize what the computer is doing step-by-step as it executes the program."

Online Python Tutor is a free educational tool that helps students overcome a fundamental barrier to learning programming: understanding what happens as the computer executes each line of a program's source code. Using this tool, a teacher or student can write a Python program directly in the web browser and visualize what the computer is doing step-by-step as it executes the program.